<template>
	<el-breadcrumb class="app-breadcrumb" separator="/">
		<transition-group name="breadcrumb">
			<el-breadcrumb-item v-for="(item, index) in levelList" :key="item.path">
				<span v-if="item.redirect === 'noRedirect' || index == levelList.length - 1" class="no-redirect">{{ item.meta.title }}</span>
				<a v-else @click.prevent="handleLink(item)">{{ item.meta.title }}</a>
			</el-breadcrumb-item>
		</transition-group>
	</el-breadcrumb>
</template>

<script>
export default {
	data() {
		return {
			levelList: null,
		};
	},
	watch: {
		$route(route) {
			// if you go to the redirect page, do not update the breadcrumbs
			if (route.path.startsWith('/redirect/')) {
				return;
			}
			this.getBreadcrumb();
		},
	},
	created() {
		this.getBreadcrumb();
	},
	methods: {
		getBreadcrumb() {
			// only show routes with meta.title
			let matched = this.$route.matched.filter((item) => item.meta && item.meta.title);
			const first = matched[0];

			if (!this.isDashboard(first)) {
				matched = [{ path: '/index', meta: { title: '首页' } }].concat(matched);
			}

			this.levelList = matched.filter((item) => item.meta && item.meta.title && item.meta.breadcrumb !== false);
		},
		isDashboard(route) {
			const name = route && route.name;
			if (!name) {
				return false;
			}
			return name.trim() === 'Index';
		},
		handleLink(item) {
			const { redirect, path } = item;
			if (redirect) {
				this.$router.push(redirect);
				return;
			}
			this.$router.push(path);
		},
	},
};
</script>

<style lang="scss" scoped>
.app-breadcrumb.el-breadcrumb {
	display: inline-block;
	font-size: 14px;
	line-height: 50px;
	margin-left: 8px;

	.no-redirect {
		color: #97a8be;
		cursor: text;
	}
}
</style>
